Hypothetical example of a screening hold which would not be an untoward event:
Everyone is living longer.
Trial is substantially enrolled but because every one is living longer it looks like it will take much longer than expected for events to occur.
Hold on screening and enrollment because they do not want to further delay the trial and data coming out of the current patient population appears to be adequate for approval.
LOL.
In your example the hold would slow down the results, not speed them up.
Further, you are changing the trial based on known results. Which is a huge no-no.
And lastly, the FDA would not need to place a hold to do this. The sponsor could simply stop enrolling.
The FDA hold is a major problem, and everybody who is not smoking hopeium knows it.